I'll be the first to admit that I'm not one in favor of this change, not when I see higher priority issues that (in my humble opinion) should have been addressed first. However, I am willing to at least give it a chance, simply because I love the game so much.
What I'll do is cut down on my number of teams by dropping the ones that have no "sentimental value" to me, keep the ones that do, and then go from there when the update is rolled out. If at that point I don't like it then I will gradually phase the rest of my teams out. If I do think the change is worth continuing to play, then I'll keep the sentimental teams and think about rejoining the worlds that I initially left. Seems easy enough.